Today's mobile devices often have the capability to access wireless fidelity (Wi-Fi) networks, such as those defined by Alliance Hotspot 2.0 technical specification release 2 version 1.02 (Hotspot 2.0, rel. 2, v1.02), which is incorporated herein by reference. Typically, a mobile device may engage in an On-line Sign Up (OSU) process to gain access to a Wi-Fi network. The OSU process may allow the mobile device to subscribe to the network as well as to be provisioned network access credentials for secure access. Different protocols may be used for OSU depending on the capabilities of the mobile station as well as the base station. Accordingly, mechanisms for advertising and selecting OSU protocols are needed so that mobile devices may access Wi-Fi networks.